Question concerning your first paragraph:
>>>>> You sais: "If the force you apply to the ball, as you're saying, is F= MA, and the batspeed is constant, this means acceleration is zero, therefore the force is zero! With no acceleration, F becomes zero, because anything multiplied by zero, is still ZERO!" >>>>>

Clairfy this: I understand that if A=0, F=0 also. But unless A=V (velocity) I think you didn't swing.

>
>>>>Steve: If the bat could move faster after contact than before contact (which is impossible), you've struck the ball with less than maximum batspeed. You have to look at it as a moment in time (for all practical purposes, the changes in the speeds of bat and ball are instantaneous.) The bat instantaneously loses momentum and the ball instantaneously gains some."

Response: I view this (acceleration through the ball) as a coaching cue and do understand (better now) the true physics. However, it is not too simple a statement to say that the ball gained momentum. Did the ball not come to a complete 0-MPH stop before reversing itself on it's new path. Please explain the instantaneous gain of momentum with a complete reversal. (Transfer of inertia?)